The Third Generation Partnership Project 2 (3GPP2) Code Division Multiple Access (CDMA), known as 3GPP2 cdma2000, networks support packet data and circuit switched voice communication. The original system supports packet data and circuits switched voice communication and is commonly referred to as the cdma2000 1X system. The cdma2000 1X system air interface is standardized in 3GPP2 document C.S0001 through C.S0005 and corresponding Telecommunication Industry Associates (TIA) standard TIA-2000. In addition, new packet data standards, such as cdma2000 High Rate Packet Data (cdma2000 HRPD) have been created. The cdma2000 HRPD air interface is standardized in 3GPP2 document C.S0024-B. To ensure communication continuity for a mobile radio communication device moving between overlaid 1x and packet data networks, it is desired to provide Cross-Paging capabilities that enables a mobile unit to be notified of incoming 1x circuit voice calls, or Short Message Service (SMS) messages when the mobile is operating on the HRPD network.
A 3GPP2 Radio Access Network (RAN) to support cross paging consists of an Mobile Switching Center (MSC), a 1x BS (Base Station), an HRPD AN (Access Network or Access Node), an HRPD PCF, and a Packet Data Serving Node (PDSN) and is standardized for two different RAN architectures in 3GPP2 A.S0008-B (see FIG. 1) and A.S0009-B (see FIG. 2). An interworking system (IWS) function has been introduced in 3GPP2 for connecting a HRPD system with a 1X system.
In addition, 3GPP2 C.S0024-A supports the Secondary ColorCode where an HRPD AN broadcasts the ColorCode used by neighboring ANs. The use of the Secondary ColorCode allows a dormant mobile to move between subnetworks of AN/PCFs that advertise overlapping ColorCode without performing registration. Proposals have been made to let an AN/PCF request a neighboring AN/PCF to transmit a page on its behalf, i.e. inter-AN paging. However, cross-paging from the 1x system to the HRPD system will fail when Inter-AN paging is used (or SecondaryColorCode support is enabled). Since the mobile does not perform registration in new subnetwork, the 1x system will use the source subnetwork to do the cross-paging. This will cause the cross-paging to fail, since the mobile is in the new subnetwork. Moreover, current Inter-AN paging may not work, since the current technique does not transfer session information to target AN.
One proposed solution is to send the Cross-Paging request to both AN/PCFs, i.e. the first (source) subnetwork where the mobile station registered and the second (target) subnetwork where it has moved. However, this proposal does not work since only the AN/PCF of the first subnetwork has the Circuit Services Notification Application (CSNA) configuration for the mobile. The AN/PCF of the second subnetwork does not have the CSNA configuration for the mobile. Therefore, the CSNA state in the AN/PCF of the second subnetwork is in “Inactive State”, which prevents sending any CSNA message to mobile.
Another proposed solution is to use existing Inter-AN paging. This proposal uses existing Inter-AN paging mechanism, i.e. source AN/PCF to send a Paging Request message to a target AN/PCF, then target AN/PCF sends the HRPD Page message to mobile. However, the current HRPD Page message does not contain the Cross-Paging information. Therefore, when the mobile receives the Page message, it will start the normal procedure, i.e. establish the session with the target AN/PCF, perform session transfer, and then perform 1x registration. This requires time to register. In addition, the 1x system may re-start the cross-paging delivery. But this will take several seconds till 1x system knows that the mobile is in the target subnetwork, which may cause 1x page timer out. As a result, the currently proposed solutions cannot solve the problems mentioned above.
What is needed is a new technique to provide Inter-AN paging. More, particularly, it would be of benefit to provide an extended Inter-AN paging procedure to support 1x to HRPD cross-paging in neighboring ANs, while reducing the number of registrations by the mobile station.
Skilled artisans will appreciate that common but well-understood elements that are useful or necessary in a commercially feasible embodiment are typically not depicted or described in order to facilitate a less obstructed view of these various embodiments of the present invention.